This is about the storage model of the 2225, the 2225 ST. I have found a forum of someone in Germany selling a 2225 ST, which proves the existence of such an oscilloscope. An image is included, but the resolution is low. But looking through the pixels, you can see it resembles a 2225 but also has buttons above the trace positioning controls for the y-axis, similar to other 2000 series DSOs.
Link to the forum: https://www.flippermarkt.de/community/forum/threads/tektronix-2225-st-2x-50-mhz-speicheroszilloskop.257775/
Can someone find a better image?
Stupid me didn't scroll down enough on the wiki page and didn't see the other images added.